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Show jLiing south, the Mule Ear stands as one of the area's most prominent features. bjamonds in Southeastern Utah? Bt Akin Reiner pumonds in southeastern '.ah? IV possibility of these ; stkling jewels being found j jot completely being dis-' dis-' Icsted, b"t it is rather ' 3ely. This is according to Frincis R. Boyd, the head if geophysical lab of the iiegie Institute in Wash- jm. D.C. Dr. Boyd and close to 100 tsxijtes recently spent a spleof days visiting an area called Moses Dike at the base of the Mule Ear, which is located several miles south of the San Juan River along Comb Ridge. Throughout the trip massive and elaborate scientific terms were thrown about by these penologists and geophysicists from all over the world. In fact, the countries represented were almost as numerous as those in the United Nations, with eminent gologists from Japan, the Soviet Union, South Af- l ! V .1 ; . y.. Francis R. Boyd heads the Carnegie Institution's physical Lab and organized the field trip. He feels at the odds of finding diamonds near the Mule Ear 2d Moses Dike are a hundred to one, but places like 2s are of great value to the scientist. (Photos by Alvin iiiner) rica, Australia, Venezuela and Brazil, to name a few. Two terms which were repeatedly re-peatedly used were Kimber-lite Kimber-lite and diatreme. The former derives its name from the Kimberly diamond mines in South Africa, and is composed of ground-up rock fragments and dust from 150 to 200 kilometers below the Earth's surface. A diatreme, on the other hand, is a vent through which these particles travel after the subterranean explosion explo-sion takes place. The field trip was arranged to allow the scientists to view one of the few exposed diatreme dia-treme formations in the United Unit-ed States. According to studies stud-ies done during six summers by Dr. Thomas R. McKetchin, who is now the Director of Lunar and Mars Research in Houston, the explosion at Moses Dike took place between be-tween thirty and fifty million years ago. It started approximately approxi-mately 175 kilometers beneath be-neath the Earth's surface, where the temperature is around 1000 degrees Centigrade,, Centi-grade,, and the pressure is close to 60,000 atmospheres. Under these conditions the rock is still solid. This is different from the usual volcano, vol-cano, as no melting of the rock occurs. The eruption might be considered a violent volcano, as there is a tremendous tremen-dous force which propels the materials at 300 to 400 meters a second. Rocks as large as 10 meters in diameter are ejected eject-ed to the Earth's surface. The rocks, which are from the upper Mantle, can readily be discerned, as they are several times heavier and harder than the indigenous shales and sandstones of the surface. The rocks derived from a depth of a few kilometers are mostly granite and gneiss, while those obtained from greater depths are classified as "ultra-basic." "ultra-basic." Some of the rocks may be two billion years old. According to Dr. Boyd, the Kimberlite pipes in southeastern south-eastern Utah have yielded no diamonds so far, and thus are of no economic importance.- However, they are valued in the scientific community. One of the primary reasons for studying Moses Dike, which is about four miles long and one thousand feet wide, is the fact that it is exposed rather than covered by another formation or vegetation. This type of formation is the main source of information as to what is in the center of the Earth, since man cannot drill to the depths from which these rocks came. Another area which the geologists visited was near Virginia Dam, on the Colorado-Wyoming border, where some diamonds were discovered discov-ered two years ago. Most of the world's diamonds dia-monds are derived from India, Brazil and South Africa, with the latter producing 95 percent per-cent of the supply. The only commercial mine in the United Unit-ed States was situated at Murfreesboro, Arkansas, and has now been transformed into a state park. After the trip to Moses Dike, the scientists headed for Santa Fe, New Mexico to attend the Second International Interna-tional Kimberlite Conference, in which another hundred or so experts would participate. The first conference was held in South Africa in 1973, with the next one scheduled for Brazil. The San Juan Field trip was conducted by Kenny Ross of Wild River Expeditions of Bluff, and Mitch Williams, proprietor of Tag-A-Long Tours in Moab, who took the geologists to various other points of interest during a float trip down the San Juan River. |